JPH035242A - Breather device for irregular ground traveling vehicle - Google Patents

Abstract

PURPOSE:To prevent damage in the sealing part or the like of a case due to the pressure fluctuation inside the case, in a breather device of a closed case such as a closed-type brake and a gear case, by constituting the device so that the pressure inside the closed case can be always maintained at the atmospheric pressure. CONSTITUTION:In a closed-type drum brake 20 provided at the end of the rear wheel axle of the title vehicle, the brake case 21 thereof is fixed to the axle sleeve 15 (not shown), and the brake drum 22 is connected to the rear wheel axle and to the rear wheel 6 so as to be integrally rotated. In this case, an opening 28 is formed in the brake case 21, and thereto a first breather pipe 30 is fitted. And a tank 32 comprising a tank body 33 to the upper part of which openings 34, 35 are provided is fitted to the vehicle frame part at the front, and an one-way valve 36 allowing only the outflow of water is provided at the lower part of the tank body 33. And to the opening 34, the other end of the first breather pipe 30 is connected, and also to the opening 35, one end of a second breather pipe 31 the other end 31a of which is connected to the atmosphere at the upper part of the vehicle body is connected.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a breather device for a closed case such as a closed brake or gear case in an all-terrain vehicle.

2. Description of the Related Art In recent years, vehicles for traveling on rough terrain, generally referred to as buggy vehicles, have become popular as leisure or practical vehicles. This vehicle is a two-wheeled or four-wheeled vehicle equipped with L7 low-pressure wide tires called balloon tires, and it runs on rough terrain.
You can also cross swamps, etc.

Such vehicles for traveling on rough terrain employ sealed brakes to prevent water from flowing into the brake case when traveling underwater. However, if the air pressure inside the brake case changes due to a temperature change, a load is placed on the sealing portion, so attempts have been made to communicate the inside of the brake case with the atmosphere. This also applies to the gear case of the final reduction gear when a shaft drive system is adopted as the wheel drive system, and the inside of the gear case is communicated with the atmosphere.

However, since water flows in from these atmospheric communication parts during underwater driving, as shown in FIG. By positioning it above line A, water is prevented from flowing in.

(Refer to Japanese Patent Publication No. 63-65532) Specifically, in the shaft drive type rough terrain vehicle 01,
Connect the breather pipe 02 to the gear case 03 of the final reduction gear, and run the breather pipe 02 along the drive shaft cylinder 04 through which the shaft passes.
2 is arranged and further extended upward, and its opening end 02a to the atmosphere is above line A and is directed downward to prevent rainwater from entering.

Under normal circumstances, the breather pipe 02 with this structure allows the inside of the sealed brake or gear case to be communicated with the atmosphere and to prevent water from entering. Due to the environment in which the vehicle is used, the vehicle may be driven in deeper water, in which case water will flow into the sealed drum brake or gear case from the breather pipe.

Furthermore, when the drive is stopped at night, condensation occurs inside the pleaser pipe.
The water may accumulate inside the sealed brake or gear case.

The present invention relates to an improvement of a breather device for an all-terrain vehicle that overcomes these difficulties, and includes a breather pipe to avoid pressure fluctuations in a closed case such as a closed brake or gear case. In a breather device for an all-terrain vehicle, the breather pipe consists of a first breather pipe and a second breather pipe, one end of the first breather pipe is communicated with the inside of the sealed case, and the other end is connected to the upper part of the sealed tank. The tank is characterized in that one end of the second breather pipe is connected to the upper part of the tank, the other end is opened to the atmosphere at the upper part of the vehicle body, and a drainage means is provided in the lower part of the tank. be.

Since the present invention is configured as described above, even if the rough terrain vehicle repeatedly accelerates and decelerates, and the temperature in the sealed case such as a sealed brake or gear case increases and air expands, Since the inside of the sealed case is always in communication with the atmosphere through the first breather pipe and the second breather pipe, the air inside the sealed case is released to the atmosphere through the first breather pipe and the second breather pipe, and the pressure inside the sealed case is reduced. held at atmospheric pressure.

Further, in the present invention, even when the airtight case is cooled by water and the air in the airtight case contracts when the rough terrain vehicle crosses a swamp or a river, the first breather pipe and the second breather pipe Air from the atmosphere is sucked into the sealed case through the breather pipe, and the pressure inside the sealed case is maintained at atmospheric pressure.

Furthermore, in the present invention, even if water flows into the second breather pipe, it remains temporarily in the tank and is discharged by the drainage means at the bottom of the tank. Water will not enter into sealed cases such as brake or gear cases.

Ura-Taneichi ■ An embodiment of the present invention illustrated in FIGS. 2 to 5 will be described below.

The vehicle for traveling on rough terrain 1 has a saddle-type seat 2 on the upper part of the vehicle body.
It is equipped with a fuel tank 3, a bar handle 4, and a pair of front wheels 5 and rear wheels 6 each having low-pressure wide balloon tires at the front and rear.

Further, the frame of the vehicle body is formed of a pipe frame 7, and an engine 8 is supported approximately at the center in the longitudinal direction.

Further, the output from the engine 8 is configured to be transmitted to a drive shaft 10 that passes through a drive shaft cylinder 9b that forms a part of the rear fork assembly 9 that can swing around a swing shaft portion 9a. The drive shaft 10 is integrally and rotatably connected to a final drive gear 12 rotatably supported within a gear case 11.

Furthermore, the gear case 11 has a seal portion 16.17.1.
8, and is filled with lubricating oil.

Inside the gear case 11, a final drive gear 12 is meshed with a final driven gear 13 that can rotate integrally with the rear axle 14, and transfers the driving force from the engine 8 to the rear axle 14.
It is intended to be communicated to

Further, the rear axle 14 is rotatably supported by the axle cylinder 14, and rotates the rear wheel 6 integrally.

On the other hand, a sealed drum brake 2 is provided on the right end of the rear axle 14.
0 is set.

The brake case 21 of the sealed drum brake 20 is fixed to the axle cylinder 15 with bolts, and the brake drum 22 is coupled to the rear axle 14 and rear wheel 6 so as to rotate together.

Further, the adjacent portion between the brake case 21 and the brake drum 22 is made air-water tight by a seal portion 23.

Furthermore, two brake shoes 25 are mounted inside the brake case 21 so as to be able to swing around an anchor pin 24 in opposition to each other, and a brake cam 26 provided through the brake case 21 rotates. As a result, the brake shoes 25 are pushed outward against the biasing force of the spring 27 and come into contact with the inner peripheral surface of the brake drum 22 to perform a braking action. Also spring 27
is biased inward to separate the brake shoe 25 from the inner peripheral surface of the brake drum 22.

Moreover, an opening 28 is formed in the brake case 21, and the inside and outside of the brake case 21 are communicated with each other.
8, a first breather pipe 30 is attached.

Further, a tank 32 is attached to the front vibe frames 7b and 7c, and the tank 32 is composed of a tank body 33 having an opening 34, 35 formed in the upper part and a one-way valve 36 provided at the lower part of the tank body 33. ing.

The one-way valve 36 only allows water to flow out from the tank body 33.

Further, the first breather pipe 30, which has one end communicating with the inside of the sealed drum brake 20, is supported by the vibe frame 7a located above the rear fork assembly 9, and has the other end communicating with the upper opening 34 of the tank 32. .

On the other hand, the second breather pipe 31 has one end connected to the upper opening 35 of the tank 32, and the other end 31a opened downward to the atmosphere at the upper part of the vehicle body.

The embodiment shown in FIGS. 2 to 5 has the above-described configuration, and the off-road vehicle 1 repeatedly accelerates and decelerates, and the temperature inside the sealed drum brake 20 reaches -F. Even if the rising air expands 7, inside the sealed drum brake 20, the first breather pipe 30 and the second breather pipe 3
1, the pressure inside the sealed drum brake 20 is maintained at atmospheric pressure.

Furthermore, when the uneven terrain vehicle 1 crosses a swamp or a river, the sealed drum brake 20 is cooled by water and the air inside the sealed drum brake 20 contracts. The pressure within 20 is maintained at atmospheric pressure.

Even when water flows in from the second breather pipe 31, the water temporarily remains in the tank body 33, and the one-way valve 36 opens due to the weight of the condensed water, and is discharged to the outside. . Therefore, water flowing in from the second breather pipe 31 flows into the first breather pipe 31.
No water enters the breather pipe 30 and therefore no water flows into the sealed drum brake 20.

Another embodiment is illustrated in FIG.

The gear case 11 is formed with an opening 11a passing through the inside and outside, and the first breather pipe 40 is attached to the opening 11a. Although the opening 11a is shown on the side in the drawing for ease of understanding, it is desirable that it be located on the upper side as much as possible.

The first breather pipe 40 extends from the rear fork assembly 9 to the upper opening 34 of the tank 32, which is supported by the upper vibe frame 7a and has the other end attached to the vibe frames 7b and 7c.
is connected to. On the other hand, the second breather pipe 41 has one end connected to the upper opening 35 of the tank 32, and the other end 41a opened downward to the atmosphere at the upper part of the vehicle body.

The embodiment shown in FIG. 6 is constructed as described above, and even if there is a thermal fluctuation in the gear case 11, the same effect as in the case of the sealed drum brake 20 in the embodiments of FIGS. 2 to 5 is applied. In the gear case 11, the first breather pipe 4
0. The inside of the tank body 33 communicates with the atmosphere through the second breather pipe 41, so it is maintained at atmospheric pressure and the seal part 16
．． 17.18 is damaged and water cannot enter.

Even when water flows in from the second breather pipe 41, the water remains temporarily in the tank body 33 and is discharged to the outside through the one-way valve 36 due to the weight of the water itself. Therefore, water flowing from the second breather pipe 41 does not enter the first breather pipe 40, and therefore water does not flow into the gear case 11.

Furthermore, as another embodiment not shown, one end of the first breather pipe is installed inside both the sealed drum brake 20 and the gear case 11 at the same time, and the other end is communicated with the upper opening 34 of the tank body 33. Good too. In this case, even if two first breather pipes are used, one for the sealed drum brake 20 and the other for the gear case, both ends of one pipe may be
You may also use techniques that are divided into books.

In the case of this embodiment, pressure fluctuations inside both the sealed drum brake 20 and the gear case 11 can be prevented at the same time.

Yet another embodiment is shown in FIG.

In this embodiment, tank 52 is mounted on rear fork assembly 9.

A first breather pipe 5 is provided at the upper part of the tank body 53, respectively.
0 and the second breather pipe 51 are formed, and a one-way valve 56 is provided at the bottom, and the structure is the same as that of the tank 32 of the previous embodiment.
Since it is attached to the rear fork assembly 9, a horizontally elongated shape is desirable.

In the above embodiment, the sealed drum brake 20 has a brake shoe 25 actuated by a brake cam 26, but the brake shoe 25 may be actuated by a hydraulic cylinder.

Further, instead of the sealed drum brake 20, another type of sealed brake may be used.

Furthermore, although the vehicle 1 for traveling on rough terrain is a four-wheeled vehicle, it may be a three-wheeled vehicle with one front wheel.

As described above, in the present invention, the pressure inside the sealed case such as a sealed brake or gear case is always maintained at atmospheric pressure, thereby preventing damage to the seal part of the case due to pressure fluctuations inside the case. Moreover, since the pressure inside the case is maintained so as not to drop below atmospheric pressure, water intrusion into the case due to the pressure difference is prevented.

Furthermore, in the present invention, even if water enters the breather device, the water does not enter into the sealed drum brake or gear case, so the durability of the brake and gear can be improved.

[Brief explanation of drawings]

FIG. 1 is a side view of a conventional off-road vehicle equipped with a breather device with the left rear wheel removed, and FIG. 2 is a side view of an off-road vehicle equipped with a breather device according to an embodiment of the present invention. A side view of the vehicle, Figure 3 is a horizontal sectional view taken along the line ■-■ in Figure 2, Figure 4 is a longitudinal sectional view of the sealed drum brake and a longitudinal sectional view of the tank, and Figure 5 is a horizontal sectional view taken along the line ■-■ in Figure 2. ■-V in Figure 4
6 is a horizontal sectional view corresponding to FIG. 3 according to another embodiment and a longitudinal sectional view of the tank, and FIG. 7 is a longitudinal sectional view of a tank according to another embodiment. A side view corresponding to the figure. 1... Vehicle for traveling on rough terrain, 2... Bifurcated seat,
3... Fuel tank, 4... Bar handle, 5...
Front wheel, 6... Rear wheel, 7... Pipe frame, 8... Engine, 9... Rear fork assembly, 10... Drive shaft, 11... Gear case,
12... Final drive gear, 13... Final driven gear, 1
4... Rear axle, 15... Axle tube, 16.17.18
... Seal part, 20 ... Sealed drum brake, 2
1... Brake case, 22... Brake drum,
23... Seal portion, 24... Anchor pin, 25.
...Brake shoe, 26...Brake cam, 27.
... Spring, 28... Opening, 30... First breather pipe, 31... Second breather pipe, 32... Tank, 33... Tank body, 34. 35... Opening, 36
... One-way valve, 40 ... First breather pipe, 41
...Second breather pipe, 50...First breather pipe, 5
1...Second breather pipe, 52...Tank, 53...
・Tank body, 54.55...Opening, 56...One-way valve.

Claims (1)

[Claims] In a breather device for an all-terrain vehicle having a breather pipe to avoid pressure fluctuations in a closed case such as a closed brake or gear case, the breather pipe is composed of a first breather pipe and a second breather pipe, and the first breather pipe is One end of the pipe is communicated into the sealed case, the other end is communicated with the upper part of the sealed tank, one end of the second breather pipe is communicated with the upper part of the tank, and the other end is opened to the atmosphere at the upper part of the vehicle body. A breather device for a vehicle traveling on rough terrain, further comprising a drainage means provided at a lower part of the tank.